Sodium trans-bis(methyliminodiacetato-O,N,O)chromate(III), Na[Cr(C5H7NO4)(2)]

In the title compound, Na[Cr-III{RN(CH2CO2)(2)}(2)], where R is CH3, the methyliminodiacetate anions function as tridentate ligands defining a slightly distorted octahedral coordination at the Cr-III ion, with the N atoms in a trans configuration. The Cr-N distance of 2.060 (2) Angstrom is slightly shorter than the values found in the complexes where R is bulkier, i.e an isopropyl or tert-butyl group, whereas the Cr-O bond lengths vary little as the size of R is changed. The methylimino-diacetato derivative appears to be the most symmetrical of the substituted iminodiacetato complexes so far studied.